Degree of mineralization at the attachment of lateral pterygoid

The degree of mineralization of bone (DMB) in the human mandibular condyle is heterogeneous, and differences in DMB have been related to variations in bone turnover caused by local strains. The lateral pterygoid muscle inserts at the anterior surface of the condyle. The aim of this study is to analyze the DMB at the attachment of this muscle as compared with a control region. It was hypothesized that, DMB at the attachment sites of lateral pterygoid muscles was lower than at the control regions, because of the larger number of loadings and subsequently higher remodeling rates. Also, as the human lateral pterygoid muscle is heterogeneous in its internal architecture, variations in DMB within the attachment sites were expected. 10 human mandibular condyles were scanned in a micro CT system. Within each condyle, two regions, that is, the pterygoid fovea and a posterior (control) region where no muscle was inserted, were selected to analyze regional differences in DMB. The attachment site was further divided into eight subregions to analyze subregional differences. At the pterygoid fovea the DMB of cortical bone was significantly lower than at the control region (p = 0.003) and increased in medio-lateral direction. The results of this study could suggest an influence of the lateral pterygoid muscle on bone turnover at this site.